Pressure resistant vessel



H BIRCHALL PRESSURE RESISTANT VESSEL 2 Sheets-Sheet 1 Filed Dec. 28,1940 FIG.3.

FIG.

INVNT-O-R Y NM? WE FIG. 2

ATTORNEY 17, 1944. H. BlRcl-IALL PRESSURE RESISTANT VESSEL Filed Dec.28, 1940 y2 Sheets-Sheet 2 E I l2 f n 4 u f r FIG.. 6.

FIG. 5

mvac'ron HAROLD BIRCHALL 4 Bf K .s m so AT TORN Passed e 111,9# fl2,360,391

readily available and cheap form.

" UNITED "srle'rissI PATENT [OFFICE i PRESSURE rztg'fm'r vEssEL v Harold`ii'chall, Norton-on-Tees, England, asv signor; to Imperial ChemicalIndustries Limited, a corporation of Great Britain .Appucaticn December2s, 1940, serial Nc. avales InGreat Britain December 28, 1939 9 Claims.(Cl. 220'-3) This invention relates to cylindrical vessels 'I'he hollowcylinder may be a forging, which, of substantial diameter adapted towithstand however, is lighter and simpler to make than the high internalfluid pressure, e. g., 50atmospheres usual type since it may bein theform of a simple or over, one or both ends being ttedwith covers.cylinder Without the large end flanges hitherto Hitherto it has-beencustomary to make such necessary to take theload on the end covers.vessels from solid forgings and to attach the Moreover, it requiressmaller lifting gear for incovers to the body of the vessel in such away stallation and removal since Ait can be moved that its walls notonly withstand the hoop stress independently of the tiefbel'sdue tointernal fluid pressure, but also the end Alternatively the hollowcylinder may adi/anta; load exerted on the covers by the' internal fluid10 geously be built up in the form of an inner tube pressure. reinforcedto withstand high internal pressure This construction has of necessitybeen very by one orl more external elements such as coexpensive becauseof the large amount of metal axial enveloping tubes. Theinner tube mayitselfv which has to be rejected from the ingot in order Vbe built 11pfrom plate or sheet by longitudinal to obtain a sound forging, theAdiilicultiesl and -15 welding, or from plate or sheet wound in the'heavy outlay on plant for forging and heat treatform of a closed helix,with adjacent edges ing, and also in the case of vessels intended toWelded together. or from tWO 01 more tubes withstand chemical attack,the high cost of the welded end to end circumferentially. If desiredmaterial of construction. Large forged vessels .the -inner tube mayconsist 0f GWO Q1 more tubes of this type moreover, which may-'weigh upto 50 20 placed end to end without yany circumferential tons, have thedisadvantage that they necessitate welds, but with sealing gasketsbetween adjacent the installation of heavy lifting gear for their ends.v e installation and removal for overhaul. A feature of the presentinvention consists in It has also been proposed to build up cylintheprovision of a particularly advantageous form ders ofthe necessary wallthickness from a nest f built-rip hollow cylinder, consisting of an inofconcentric tubes, to the -ends of 'which flanges ner tube and apluralityof rings of plate or sheet are 'welded to take'the end covers. In thisconmetal, each concentric with and in contact with struction, the weldsare ubjected to the full Athe inner tube. By this construction thehollow tensile load on the end covers, and therefore macylinder can bebuilt up largely or wholly from terials must be used in w ch reliablewelds of -metal in readily available and cheap forms, i.' e.,

nrst class quality can be produced. plate or sheet, with little vor nowelding which 'I'he object of the invention is to provide a will besubjected to heavy tensile loads. Each pressure resistant vessel whichhas one or more ring l'nay be 'in Contact with adjacent rings Q r of thefollowing advantages as compared with may be spaced apart from them, themaximum known pressure resistant vessels. 35 permissible distancebetween adjacent rings tie-- '1. Construction at least in part frommetal in' ing dependent upon the thickness of the inner tube and theinternal pressure to which it is to 2. Quicker construction. v Vbesubjected. v

3. Few or no welds which are subject to heavy When employing thebuilt-up construction of tensile load. 4o cylinder, the reinforcingelements may be shrunk 4. Smaller lifting gearrequired for installa-V onthe inner tube to reduce or even eliminatev tion and remov the hoopstress at its internal surface-when in 5.'Smaller amount -of specialalloys to resist use, so that an inner tube made from sheet or.

Vinternal chemical attack. plate metal. by longitudinal welding canconm-' 6. Smaller stresses Vat the intemal4v surface of 45 dentlyv beused. Moreover, when the vessel is the Pressure ves to containsubstances which attack the inner Ihe pressure resistant vessel of thisinvention tube, the reduction in stress in the inner tube comprises ahollow cylinder adapted to withstand attained by shrinking on thereinforcing mem- 'the hoop stress due to the said uidpressure, berstends to diminish the rate of attack.

covers forv the ends ofthe cylinder, and tie-bars 'I'he built-upconstruction 0f Cylinder has the 'external to the cylinder, adapted torelieve the vfurther advantage that the inner vtube may be cylinder oftensile load due to internal uid presmade 'of diil'eren't metal from thereinforcing sure on the end covers and to hold the covers elements.-Thus, the latter may be made of a in Huid-tight Contact with the endsofthe cyl- ,high tensile alloy steel, while the inner tube may ndelc 55be made of metal chosen to resist any chemical anges to form a sincethey will be subject only to small stresses.

it and towards the other end of the vessel counl of the ring, it ispossible the internal uid pressure.

v1y to the covers which then attack to which it might be subjected inuse, e. g., of an alloy steel resistant to attack by hydrogen at highpressure and elevated temperature.

In a modification thecylinder may be formed with a permanently closedend, e. g., by welding a plate n to it. In this case a cover plate towhich the tie-bars are connected preferably bears against the closed'end and reinforces itl against It is also possible permanently to sealone end of the cylinder by means of a plate of sufficient strength towithstand the internal iiuid pressure, the tie-bars being connected tothe said plate.

The external tie-bars may be connected directare provided with lugs orextend beyond the 'walls of the cylinder, or may, be connected to crossbars which bear against the external face of the covers. The connectionsbetween the cross'bars and the tiebars are advantageously solid, thatis, the cross bars and tie-bars are integral in the Iorm of arectangular frame. The cross bars and the tiebars whether separate orintegral may be solid, but they are preieraV ly laminated, that is,built up of a plurality of juxtaposed plates. Thus, in the caseofintegral tie-bars and cross-bars, they may be built up of a plurality ofjuxtaposed frames of sheet metal, while in the case of separate tiebarsand cross-bars, the tie-bars may each consist of a plurality ofjuxtaposed tie plates, and the cross bars may each consist of aplurality of juxtaposed metal'plates each of which extends across thecover from one' tie-bar to another.

Any suitable known means may be used for sealing the joint between thecovers and the 5 cylinder. For examplethere may be employed y a jointring of the type whichseals by radial` pressure against the inner wallof the inner tube,

or a joint ring which ts between the cover and w the end of the innertube. When the latter type of joint ring is employed, the ends of theinner tubes are preferably provided with internal suitable seat'. rIheseanges may be welded on ,to4 the ends of the inner tube,

When the inner tube is provided with internal flanges, it is preferredto use a sealing ring of C section, so that the fluid pressure'acting-inside teracts the uid pressure acting outwardly on the flange. Bysuitable choice of the dimensions to balance the pressures on oppositefaces of the flange, thereby relieving the inner tube of longitudinalstress.

Alternatively, if desired, the inner tube may be made to carry a part ofthe longitudinal stress,- thereby reducing the end load to be taken bythe tie-bars, by providing the inner tube with an internal ange andusing a joint ring of smaller diameter than the bore of the inne'rtube.If desired, the inner tube may be subjectedto compressive stress by'providing it with anexternal flange and using a-joint ring of greaterdiameter than the bore of the tube. I v In closing the vessel, theinitial sealing pressure on the Joint between the covers andthe cylindermay be conveniently obtained by heating the tie bars, e. g., by means ofelectril windings,V taking up the slackness-thereby produced, for'example, when crossibars-are used, by inserting' packing pieces betweenthem and the cover's, and` then allowing the cross bars to cool.

Four forms of the invention are illustrated in position nated cross-bars9 the ends of that the invention lFigure l is a sectional-elevation of apressure mesistant vessel the covers of which are held in positionbymeans of laminated cross bars and separate laminated tie-bars;

Figure 2 is a plan view of the vessel of Figure l;

Figure 3 is a sectional elevation of a pressure resistant vessel thecovers of which are held in by means of laminated frames consisting ofintegral cross bars and tie-bars;

Figure 4 is a plan view of the vessel of Figure 3.

Figure 5 is a' sectional elevation of a pressure resistant vessel thecylinder of which is provided at its ends with internal' ariges whichform a seat for sealing rings.

Figure 6 is a sectional elevation of a pressure resistant vessel havingone open end, and

Figure 7 is a fragmentary andenlarged view of the lower portion ofFigure 5..

.Referring to Figures 1 `and 2, the vessel is built up of an inner tubel and a plurality of reinforcing rings 2 made from metal plates. lItwill be apparent that the reinforcing rings are preferably cut in onepiece from a sheet of plate material, thus forming ccntinuousannularmembers having an axial thickness less than their radial width. Thecovers 3, lhave annularrecesses 5, to accommodate horseshoe sealingrings 1, which bear on the flat ends 0I the tube l. T'he covers are heldin position by Vmeans `of lamiwhich engage -in holes in the ends oflaminated tie-bars l0. A, shim, indicated at I2, is interposed betweenthe bottom cross bars and the cover 4 when the tiebars have beenexpanded by heat, so that a tight joint is obtained when the tie-barscontract. Holes I3 for pipe connections are provided in the cover 3. i C

Referring to Figures 3 and 4, the covers are held in position by twolaminated frames Il each consisting of six one-piece plates. ',l'heplates are advantageously constructed by cutting from a single plate, orby weldingtogether pairs of endand side members. In other words, the tiebar and cros's bar constructions inboth of the foregoing embodiments arecomposed of. a pluralityV of vforms cut from plate or sheetmaterial anddisposed in flatwise stacked relationship.

Referring to Figure 5, the vessel is built ufp of an inner tube'l and aplurality Vci reinforcing' cylinders I6. Internal ilanges 8 areconnected to ythe ends of the inner tube l by welds 6, andv form seatsfor the sealing rings 1. Figure 7 illustrates this arrangement. f

1Referring to Figure 6,.the vessel is permanently closed vat one end bya plate l5, which is welded vto the inner tube I. The cover plate I2bearslv against the platev I5 and reinforces it against the internal uidpressure.

g As many widely different embodiments of this invention may be madewithout departing from the spirit'orscope thereof, it is to beunderstood is not limited to the speciiW embodiments thereot,.except asdonned in the appended claims.l

Iclaim: 1. 'A vessel resistant o high internal fluid pressure,comprising af tube, a plurality of reinforcing rings` of plate metalthinner than the radialwidth of the rings, mounted in stacked relation,concentric with and in contact with said tube,to brace the tube 'againsthoop stresses due to said fluid pressure, closure means for the endsofthe tube, tie bar means external to the tube, extending to adjacent theclosure means, and cross bar means secured by said tie bar means andengaging the closure means whereby to press the closure means to thetube against said fluid pressure.

2. A vessel resistant to high internal uid pressure, comprising a tube,a plurality of mutually touching reinforcing rings of plate metal'thinner than the radial width of the rings, concentric with and incontact with said tube and extending from one end thereof to the other,to brace the tube against hoop stresses due to said fluid pressure,closure means for the ends of the tube, and tie bar means external tothe tube, extending to adjacent the closure means and engaging theclosure means whereby to hold the closure means to the tube against saidfluid pressure.

' 3. A vessel resistant to high internal uid pressure comprising a tubeof a. type resistant to hoop stress, end cover means and means forretaining the cover means against internal pressure comprising aplurality of frames of plate metal assembled in laminated configurationfitted over the tube and closures, having openings of such length as toengage the cover means and of such width as to clear the tube. y

4. A vessel resistant to high internal fluid pressures comprising a tubeprovided with in? ternal anges at its ends, a plurality of reinforcingrings of plate metal thinner than the for the tube.

radial lwidth of the rings-concentric with and in contact with saidtube, to brace the Atube against hoop stresses due to said uid pressure.closure means for the ends of the tube, annular sealing means betweenthe closure means and the anges and tie bar means external to the shell,extending to adjacent the closure means and engaging the closure meanswhereby to hold the closure means against said annular sealing means.

5. A vessei resistant to high `interim fluid pressures comprising a tubeprovided with internal flanges at its ends, a plurality of reinforcingrings of plate metal thinner than the radial width of the rings,concentric with and in conand conligurated to 6. A vessel resistant tohigh internal uid pressure, comprising a tube,.aplurality of reinforcingrings of plate metal of thickness less than the radial width of therings, concentric with and in contact with the tube, whereby to bracethe tube against hoop stresses due to internal Vuid pressure, covermeans for the ends of the shell and means for retaining the cover meanscomprising a plurality of frames of plate metal assembled in laminatedconiguration ntted over the tube and cover means and having openings ofsuch length as to engage the cover means and of such width as to clearthe tube.

7. A vessel resistant to high internal uid pressure and formedsubstantially entirely from plate material, said vessel comprising atube, a plurality of reinforcing rings of plate metal thinner than theradial width of the rings and mounted in stacked relation concentricwith, andY in contact with said tube whereby to brace the tube againsthoop stresses due to said uid pressure, cover means for both ends ofthetube and means for retaining said cover means comprising a pluralityof frames. of plate metal 'arranged in stacked relationship, each ofsaid frames comprising sections extending across and outwardly beyondthe edges of the closure means and a plurality of plate metal sectionsextending longitudinally adjacent the side of the tube to form laminatedtie bars, said tie bar sections being connectedvwith said cross barsections to resist internal pressure on the closure means.

8. A vessel constructed as dened in claim 7-,

wherein said tie bar plates are separate from engage the extremities ofthe cross bar sections in operative relation.

9. A vessel resistantv to high internal fluid pressure comprising atubular hollow cylinder of a type resistant to hoop stress, end covermeans for the cylinder cover means against internal duid pressurecomtact with said tube, to brace the tube against hoopl stresses due tosaid uid pressure, closure means for the endsof the tube, annularsealing means between the closure means and the nanges and exposed topressures in the tube and so proportioned that equal loads are exerted0n both faces of `each anse bythe' nuid pressure so that the tube isrelieved of longitudinal stress due to fluid pressure; and tie bar meansexternal to the tube, extending to adjacent the closure means andengaging the closure means whereby to hold the closure meansv againstsaid annular sea1ingmeans.,. ,v f

prisinga plurality of sheet orl plate metal frames relatively thin ascompared with their width, said frames being arranged in stacked atwiserelationship and having their upper and lower inner marginal edgesadapted to engage the cover means and acting thereon' to resist internalfluid pressure on said cover means, and a plurality of continuousannular reinforcing rings of sheet l or platemetal, each embracing` thecylinder inside of said frames. said reinforcing rings being formed ofplate material thinner than the radial widthof thev ring and beingdisposed in :datwise stacked relationship concentric with the cylinderto brace the cylinder against hoop stresses due to fluid pressure.

HAROLD Braunau..

and means for retaining the,

